Furnace



April 28, 1925.

W. H. FISHER ET AL FURNACE Filed May 15, 1923 INVENTOR. William/J5 F 57127; Peier Uhaznfiens I /r a I A TTORNEYS.

Patented Apr. 28, 1925.

UNITED STATES PATENT OFFICE.

WILLIAM H. FISHER, DE LOS ANGELES, AND PETER CHAMBERS, OF REDONDO, CALIFORNIA.

FURNACE.

Application filed May 15, 1923. Serial No. 639,081.

To all whom it mag concern:

Be it known that we, VVILLIAM H. FISHER and PETER CHAMBERS, both citizens of the United States, residing at Los Angeles and Redondo, respectively, in the county of Los -Angeles and State of California, have jointly invented new and useful Improvements in Furnaces, of which the following is a specification.

V This invention relates to furnaces and method of utilizing the same for the carbon treatment of iron and its alloys. The invention contemplates an improvement over our invention disclosed in application for U, S. patent for apparatus for treating iron alloys and process thereof, Serial No. 382,290, filed in the 17, 1920. The invention has for an object the provision in a furnace of means for causmg a uniform deposit of carbon on the work contained therein.

In practicing the invention we may provide a furnace consisting of an outer refractory wall and an inner retort wall spaced therefrom, with means for supporting combustion in the space between said walls whereby the inner retort wall may be heated for the purpose of heating any workcoir fined within said inner retort and means associated withsaid inner retort and particularly the cover thereof, for admitting a liquid hydro-carbon such as set forth in our U. S. Letters Patent 'No. 1,405,678, dated February 7 1922, for composition for treating iron and its alloys.

With the above and other objects in view, the invention consists in the novel and useful provision, formation, construction, association and relative arrangement of parts, members and features,

following statement drawing.

I The drawing is a vertical sectional view of a furnace incorporating the invention.

Referring with particularity to the drawing, the improved furnace as an entirety is designated by A, and we do not wish to be and shown in the U. S. Patent Oflice May tl all as set forth in the particularly limited to the type of furnace shown, as the features about to be described" are adaptable to many types and forms of furnaces, other than the one shown for the purpose of carbonizing iron and its alloys. In particular the said furnace A includes an outer wall 1 which maybe formed of sheet steel or any other material, with a re- 5' fractory wall a formed of slabs 2 and an inner retort wall Z) spaced from the wall a, with suitable pipes 0 passed through the walls 1 and a and to the space 3 betweenthe wall I) and the inner surface of the wall a. The pipes 'cin turn are connected to a suitable gas supply main, and when the supply of gas is passed through the pipe 0 is said. gas may be ignited in the space 3, whereby combustion of said gas. The furnace is provided with a base member 4 which may carry a'heat-resisting slab or slabs 5, and upon which slabs 5 the bottom of the retort may rest. In this particular the slab or slabs are provided with shouldered portions 6 which act to confine the retort wall 6 to a definite location within the Wall a. A top member 03 .is provided which may consist of two parts as 7 and 8, the part 7 being 76 formed of sheet metal. or other material with the part 8 comprising slabs formed about the retort wall I). In the showing the retort wall 6 projects through the cover (1 and beyond said cover 0!, and adapted to be received within the retort b and to rest upon the slabs 5 is a work-holding tab-1e e comprising a top plate 9 supported by an annular member 10'formed with a series of openings 11. The top plate 9 is provided 35 with acentral opening 12, the purpose of which will be described later. A cap member f is formed with a groove 13 adapted to have received therein the upper end as 14 of the retort wall 6. Said vided with a series of transverse openings 15, and said cap is likewise formed with a central bore, as shown at 16, and adapted to be attached-to said cap 7 and received the wall 6 may be heated by the 65 cap f is pr within the bore 16 is an annular member 17.

The annular member 17 is provided with an annular end-piece 18 and an annular flange 19 fits over the member 17 with a nozzle member 20 adapted to be passed through the 0 ening in the end-piece 18 and projecting within the member 17. The said nozzle 20 is evenly spaced from the inner wall of the member 17 A union 21 connects an end of the member 20 with a tube 22, which tube in turn is connected through the medium of a union 23 with a container 24 adapted to receive and hold a liquid hydrocarbon such as described in the above men'- tioned U. S. Letters Patent No. 1,405,678. Interposed between the union 23 and the container 24: is a stop cock 25 whereby flow of liquid from the container 24 may be regulated. and likewise there is provided a second stop cook 26 associated with the member 20. It is thus possible to regulate the flow of any liquid from the container 24 through the nozzle 20 by means of the stop cocks or valves 25 and 26.

In operation, assuming that the liquid hydro-carbon as above identified is used and is placed within the container 2 1, and the furnace is being heated by means of combustion of gas within the space 3, with work stacked upon the support 6, at proper temperature the cooks 25 and 26 are opened and the liquid hydro-carbon will flow from the container through the tube 22 and thence into the nozzle 20 and there drop from said nozzle, the said cocks being so arranged that the nozzle feeds the said liquid hydrocarbon in a series of drops. The nozzle being spaced from the inner wall of the member 17 does not allow carbon to form on the inner wall of the member 17, that is to say, carbon will not form there, for the reason that the liquid drops free of the member 17 and therefore will not adhere to its sides. If the liquid did not drop free but were'allowed to contact with the inner surface of the member 17 the heat within the furnace by immediately gasifying the liquid would tend to cause carbon to deposit on said inner surface and stop operation of the device. The liquid hydrocarbon upon dropping from the nozzle 20 will gasify under influence of the heat within the retort b. The carbon separated from the hydrogen then satisfies its aflinity for absorption. by the surface of metal exposed to it.

i We provide a thermo-couple protector tube designated generally by g which projects through the opening 12 of the top plate 9, and in the showing the element 28 of such thermo-couple is a protective cover for an element 29, said element 29 comprising a bent wire to which are connected leads 3O associated with a recording pyrometer 31 calibrated in degrees, whereby when the retort b is heated through the medium of the combustion of gas within the space 3 the wire 29 will become heated and thus vary the electrical resistance and consequently actuate the recording galvanometer 31 to indicate degrees of heat within the retort b and particularly at the lower level thereof. After the heat within the retort has become approximately uniform the stop cocks 25 and 26 are opened so that the hydrocarbon liquid or carbonaceous gas is allowed to pass from the nozzle 20, in the case of liquid in drop form, with-in the retort b, and, due to the heat within said retort the liquid is immediately gasified and gaseous pressure is uniformly maintained from the top of the retort to the bottom thereof. This ensures an even distribution of carbonaceous gas within the retort and consequently produces a remarkable evenness in the results obtained in the absorption of carbon. The openings 11 in the member 6 allow heat Within the retort b to enter within the annular member'lO and tend to heat the same. VJhen it is desired to remove the work from the retort the cover may be removed by using suitable hooks in engagement with eye-bolts 32 carried by the cover 7, and before removing said cover a fixed gas is admitted by turning suitable cocks 33 through the supply pipes 27, in turn associated with the pipe 27 connected to mains delivering gas that does not contain air, the said gas eing passed through the pipes 27 under its own pressure.

Our invention involves the conception of injecting a liquid directly into the workholding chamber without substantially pre-. vaporization thereof. It is old in the art to utilize hydrocarbon gases for the cementation of steel, and these gases have in some cases been formed from hydrocarbon oils by injecting these oils into a hot vaporizing chamber, the resulting gases being then conducted to a separate work-holding chamber. Our invention differs from all such prior attempts, in that the hydrocarbon or carbonhydrate used is actually injected in liquid form directly into the work-holding chamber, being broken up in that chamber probably almost wholly into hydrocarbon gas and free carbon. We believe that the presence of this free nascent carbon greatly promotes cementation, as We have found, in the operation of a'considerable number of these furnaces, that by dropping an oil of preferably organic origin directly into the work-holding chamber, we can produce results far superior to those produced by the use of gas alone.

We also find that the apparatus above described is particularly adapted to the use of organic oils, such as pine tar or other pyroligneous products, or fish, or vegetable oils. These oils are all much less stable than petroleum, and solid and semi-solid substances, at temperatures far below thosenecessary to decompose petroleum.

By locating the inlet nozzle 20 at the top of the vertical pipe 17 we keep it far enough away from the heat of the furnace to prevent its becoming sufliciently hot to break up the oil flowing therethrough, and thus prevent solids from depositing in and clogging the opening. The pipe 17 also forms an accelerating chamber through which the drops of oil fall, and it is of sulficient length to allow the drops to attain a considerable velocity before they strike the hot gases inside the work chamber. The drops moving rapidly downward into the hot gases are vaporized by the heat, and on account of the initial velocity of the drops, the solid and gaseous resultants of the vaporization are thoroughly distributed upon and around the material being treated.

While some of the substances used by us as cementation-agents are complex carbohydrates, we wish the term .hydrocarbon as used byus herein to include such substances, and, in fact, all substances of a suit- 1able character containing hydrogen and car- It is obvious that various changes and modifications may be made in practicing the invention, in departure from the particular showing and description, without departing from the true spirit of the invention.

Having thus disclosed our invention, we claim and desire to secure by Letters Patent: 1. In a device of the character disclosed, the combination of: a retort having a workholding chamber adapted to receive the work to be treated; means for heating said retort; and means for introducing a hydrocarbon liquid into said work-holding chamber without substantial vaporization of such hydrocarbon liquid outside said wort-holding chamber.

2. In a device of the character disclosed, the combination of: a retort having a workholding chamber adapted to receive the work to be treated; means for heating said retort;

and means for introducing a hydrocarbon liquid into said work-holding chamber without substantial vaporization of such hydrocarbon liquid outside said work-holding chamber, said liquid being introduced into said work-holding chamber at a suflicient velocity to produce a dispersion of the products of vaporization over and around the work.

3. In a device of the character disclosed, the combination of: a retort having a workholding chamber adapted to receive the work to be treated; means for heating said retort;

and means for introducing a hydrocarbon liquid into said work-holding chamber without substantial vaporization of such hydrobreaking up into fixed gases dispersion carbon liquid outside said work-holding chamber, said liquid being introduced into said work-holding chamber at a sufficient velocity induced by gravity to produce a of the products of vaporization over and around the work.

4. In a device of the character disclosed, the combination of: a retort having a workholding chamber adapted to receive the work to be treated; means for heating said retort; a cover for said retort; walls forming an accelerating chamber extending above said cover and forming a continuous vertical passage in open communication at its lower end with said work-holding chamber; and means for feeding a hydrocarbon liquid into the upper end'of said passage.

5. In a deviceof the character disclosed, the combination of: a retort having a Workholding chamber adapted to receive the work to be treated; means for heating the outside retort; walls forming an accelerating chamher extending above said cover and forming a continuous vertical passage in open communication at its lower end withsaid workholding chamber; and means for feeding a hydrocarbon liquid into the upper end of said passage.

6. In a device of the character disclosed,

comprising a retort. adapted to receive and member for said reconfine work, a cover tort, said cover member being formed with openings therein, there being an annular member received within one of said openings, and a nozzle within said annular member.

, 7. In a device of the character disclosed, comprising a retort adapted to receive and confine work, a cover member for said retort, said cover member being formed with openings therein, there being an annular member received within one of said openings, and a nozzle within said annular member; said nozzle being provided with a flanged member for attachment to the annular member.

8. In a device of the character disclosed, comprising a retort adapted to receive and confine work, a cover member for saidvretort, said cover member being formed with openings therein, there being an annular member received within one of said openings, and a nozzle within said annular member; said nozzle being provided with a flanged member for attachment to the annular member; there being means for conducting a hydro-carbon liquid from a source 7 ings, and a-nozzle Within said annular mem- In testimony whereof, We have signed our ber; sald nozzle belng provlded wlth 21, names to thls SPBCIfiCatIOII 1n the presence 10 flanged member for attachment to ,the annuof two subscnbmg wltnesses.

lar member; there being means for conduct- WILLIAM H. FISHER. 5 ing a. hydro-carbon liquid from a source PETER CHAMBERS.

of supply to said nozzle, and means for- Witnesses:

regulating the flow of hydro-carbon liquid WILLIAM P. FISHER.

through said nozzle. JAMES ALLAN. 

